The April release of Risk Modeler 1.11 marks a major milestone in both model science and software. For the first time at RMS, a complete high-definition (HD) model – the RMS U.S. Inland Flood (USFL) HD model with integrated storm surge, and an accompanying model validation workflow are now available to all users on the new platform. It also marks the release of exciting new capabilities including auditable exposure edits and data access via third-party business intelligence and database tools.
What is Different About Model Validation on Risk Modeler?
For the USFL model to produce detailed insights into risk, it must realistically simulate the interactions between antecedent environmental conditions, event clustering, exposures, and insurance contracts over tens of thousands of possible timelines. That requires a new financial engine, a more powerful model execution engine, and a purpose-built database to handle the processing of and metrics calculation against the vast amounts of data that an HD model produces. Although the current RiskLink solution can perform some of these tasks and processes well and efficiently, Risk Modeler was especially built for these new requirements.
In addition to simply running this next-generation model, Risk Modeler has several features to quickly surface insights into the model and ultimately allow users to make business decisions faster.
Professor Ilan Noy holds a unique ”Chair in the Economics of Disasters” at the Victoria University of Wellington, New Zealand. He has proposed in a couple of research papers that instead of counting disaster deaths and economic costs, we should report the “expected life-years” lost, not only for human casualties but also for the life-years of work that will be required to repair all the damage to buildings and infrastructure.
The idea is based on the World Health Organization’s Disability Adjusted Life Years (DALYs) lost through disease and injury (WHO 2013). The motivation is to escape from the distortion introduced by measuring the impact of global disasters in dollars, as loss from the richest countries will always dominate this metric. Noy’s proposal converts injuries into life-years lost, based on how long it takes for the injured to return to complete health, while also factoring the degree of permanent disability multiplied by its duration. This is topped up by a “welfare reduction weight” for all those exposed to a disaster. The final component of the index attempts to capture how many years of human endeavor is lost to recovering the buildings and assets destroyed in the disaster.
There is plenty to argue over in terms of how deaths, injury and damage should be combined. In particular, the assumption that additional work to rebuild a city, is the same as a shortened life, seems somewhat reductive.
From major wildfires just over four months ago, and now major flooding, Northern California seems to leap from one perilous state to another. This time, rainfall from a “potent atmospheric river”, as described by the National Weather Service, caused flooding to over 3,000 properties in Sonoma County. This atmospheric river – a flowing column of condensed water vapor pumped up from the Tropics which can be up to 375 miles (603 kilometers) wide – started delivering rain and snow into the region late on Sunday, February 24.
The small town of Guerneville (pop. ~4,500) fared worst, reporting nearly 21 inches (529 millimeters) of rainfall in just 72 hours by 5 p.m. local time on Wednesday, February 27. The source of the town’s flooding was the Russian River, which flows from Mendocino County through to Sonoma County, reaching a maximum level of 45.5 feet (13.9 meters) at Johnson’s Beach, near Guerneville. This exceeded the defined 40 feet (12.1 meters) threshold for a major flood at this point, with local media reports stating that this is the worst flooding since New Year’s Day in 1997, when the river rose to 45 feet (13.7 meters). The nearby Napa River also crested at 26 feet (7.92 meters), one foot above the flood stage.
The town of Guerneville, which was originally built on a meander in the river, on February 27 was declared by the Sonoma County Sheriff’s Office “… [as] officially an island …” as all roads in an out of the town were flooded. 4,000 residents in both Guerneville and Monte Rio (pop. ~1,200) were under evacuation orders until Friday, March 1.
In my recent article in Reactions entitled Why Long-term NFIP Reform is a Must, I looked back at the flood events of 2018 through the lens of the need to reform the National Flood Insurance Program (NFIP). I made the argument that the NFIP is not effectively covering communities at risk or supporting the development of a private market that support that same goal.
Looking at Hurricane Florence, its impacts exemplify the type of event from which our communities need to recover from by leveraging the NFIP and a more robust private market. Both North Carolina and South Carolina each broke records for the amount of rainfall caused by a tropical cyclone. While the flooding due to storm surge was significant in areas such as New Bern, the majority of the flood damage was driven by that record rainfall in the inland areas.
The areas most impacted had the lowest take-up rates for flood insurance – the take-up rate for NFIP policies is less than two percent in the inland counties of North Carolina and South Carolina, while take-up rates in most coastal counties generally range from 10 to 25 percent. As a result, RMS analysis found that Florence caused US$3 billion to US$6 billion in uninsured losses, or about 4-5 times the losses expected to be incurred by the NFIP.
As we move full steam in to 2019, it is worth remembering that some good progress was made during 2018 with regards to advancing the private flood insurance market in the U.S. – even though Congress struggled with reform of the National Flood Insurance Program (NFIP).
Here’s five takeaway points from the past year:
1. Extending the Extension: The NFIP saw numerous extensions and a few short lapses. Just before the end of the year, Congress reauthorized the NFIP until May 31, 2019 right before the government shutdown commenced on December 22, 2018. But decisions by FEMA during the last week of the year brought uncertainty to the housing and insurance industry as it dealt with changing guidelines on whether policies could be sold or renewed during the shutdown. Ultimately, the NFIP is still operating, but the back and forth of 2018 did not bolster confidence in the stability of the program and left many asking … will 2019 be the breakthrough year?
2. FEMA Boosts the Private Flood Market: Although Congress struggled to act on the NFIP, FEMA did, with technical changes that came into force on October 1, 2018, to attract new private carriers and help existing carriers who participate in the NFIP “Write Your Own” (WYO) program.
First – removing a “non-compete” clause for carriers operating within WYO, now allows WYO carriers to offer their own private flood coverage as well as NFIP policies, with the condition that these businesses are kept separate. Second – policyholders can now cancel their NFIP policy mid-term, before its expiration date when a policyholder has obtained a duplicate policy. In combination, these steps removed hurdles that were hindering carriers from offering new flood products and making it difficult for consumers to purchase those products from the private market.
With positive changes under way to improve both public and private carrier participation across the U.S. flood market, many are looking to seize the opportunity that the U.S. flood market presents. Insurers, reinsurers, and the capital markets are exploring this opportunity which, in turn, has created a thirst for knowledge. I had the opportunity to see this first-hand when I was invited by Trading Risk magazine to take part in a panel discussion at the Trading Risk ILS: Reloaded and Resurgent event in New York last month. Sofia Geraghty from Trading Risk served as our moderator, and Joanna Syroka, Director of New Markets at Fermat Capital Management, and Ian Hanson, Vice President of Willis Re, were also on the panel.
One point that the audience wanted to understand was the level of demand to take on flood risk from an investor’s viewpoint, and also whether U.S. flood risk can be a portfolio diversifier. From the insurance-linked securities (ILS) side, Joanna confirmed the demand is there, but as with any peril, the ILS market needs to be able to clearly understand and define the risk to get comfortable enough to invest.
After a major hurricane or a similar natural disaster, RMS routinely sends modelers and engineers into the affected region to survey the destruction. This field reconnaissance in the immediate aftermath of an event serves several purposes:
Provides an indication of the most prevalent type of damage (e.g. shingle loss, structural failures, flooded contents, etc.)
Provides an indication of the general frequency (e.g. one in five homes have shingle loss) and severity (e.g. 20 percent of shingles missing) of the damage.
Helps to understand the full geographic extent of the event including the subperils (e.g. wind, surge, inland flood, etc.). As part of this effort, RMS will measure flood depths (based on visible watermarks) that help provide a sanity check for the surge and flood modelers developing the event footprints.
Talking with locals (both homeowners and businesses) provides a better understanding of the severity of the storm and the conditions immediately after an event that may have already been cleaned up before our team arrived.
Of course, RMS is always concerned about the safety of its personnel and waits until it is safe to send anyone to the disaster areas. We also have to make sure that we can travel to the different areas affected by the disaster without too much difficulty.
Florence’s much anticipated landfall occurred at 11:15 UTC (7.15 a.m. local time) today, Friday, September 14, near Wrightsville Beach, North Carolina, as a Category 1 hurricane. Florence remains just within the Category 1 hurricane classification on Saffir-Simpson Hurricane Wind Scale (SSHWS); as of the 18:00 UTC National Hurricane Center (NHC) advisory today, maximum sustained winds were 75 miles per hour (120 kilometers per hour). Previous observations showed that at Cape Lookout there were sustained winds of 83 miles per hour (133 kilometers per hour) and gusts of 106 miles per hour (170 kilometers per hour). Florence is now moving slowly toward the west at near five miles per hour (7 kilometers per hour).
Over the coming 36 hours, Florence is expected to meander into northern South Carolina and then progress further inland across the western Carolinas and into the Appalachian Mountains through the early part of next week.
The expectation that surge and inland flooding, rather than wind, would be the primary hazards associated with Florence was quickly realised as the storm approached the Carolinas coastline yesterday.
Excessive rainfall and dangerous storm surge present the greatest threat over the next few days. The potential for heavy rainfall has extended to the south and west given the change in projected track over the last 48 hours. Projections of over 15 inches (380 millimeters) of rain now cover much of southern North Carolina and northeast South Carolina — much of North Carolina is expected to receive in excess of six inches (152 millimeters) of rain.
Over the last 24 hours, the structure and forecast track of Hurricane Florence has evolved significantly as the storm begins to impact the Carolinas, but the material wind, storm surge and flood threat it poses to the Southeastern and Mid-Atlantic U.S. remains.
As of 1200 UTC yesterday (September 12), Florence’s wind field was large and powerful as the storm inched closer to the U.S. coast through favorable environmental conditions. According to RMS HWind analyses, which utilize more than 30 public and private observational data sources to generate objective, ground-truth-based tropical cyclone wind field analytics, maximum 1-minute sustained winds were estimated to be 124 miles per hour (199 kilometers per hour) (Figure 1 below), placing the storm squarely in the Category 3 range on the Saffir Simpson Wind Scale.
In addition, the Integrated Kinetic Energy (IKE), an indicator of tropical cyclone strength and damage potential, was estimated to be 104 Terajoules (TJ), putting it on par with historical events like Frances (2004), Gustav (2008), and Isabel (2003).
No hurricane landfall forecast is simple. But looking back at the forecast tracks for Hurricane Florence from the National Hurricane Center (NHC) and the ensemble members of the leading global forecast models a couple of days ago, what stood out was how relatively straightforward they were. Florence was anticipated to make a steady, assured progress directly towards the Carolinas, make landfall, and move directly inland.
In a somewhat remarkable turn of events that few, if any, models predicted 48 hours ago, Florence is now expected to stall over, or very near to, the Carolina coastline.
The huge shift in the forecast guidance is the anticipated result of a reduction in Florence’s steering flow due to two competing areas of high pressure. The hurricane is currently being steered across the southwestern Atlantic Ocean towards the southeastern U.S. around the southeastern periphery of a mid-level ridge centered northeast of Bermuda. As the system approaches land, it will come under increasing influence from a competing mid-level ridge that is forecast to begin building over the east-central United States later today. The net result of these competing steering flows will see Florence slow, meander, or even become stationary for possibly 48 hours before the system moves ashore.
This possibility could bring prolonged hurricane-force winds and storm surge throughout Saturday and Sunday, to coastal areas along North and South Carolina, and significant inland flooding to whole region.